A comprehensive neuropsychological test battery is used to provide a complete assessment of various cognitive and sensory functions that can be related to damage or dysfunction in different region of the brain. The battery comprises tests designed to tap the following aspects of behavior: executive functions, language, attention, visual-spatial capacity, memory, and motor behavior. In addition, measures of psychometric intelligence, personality, visual acuity, color vision, and hand and eye dominance are included. The battery provides a thorough assessment of the neurobehavioral capacities of the various categories of patients who are studied by investigators in the LPP. The data thus provide a complete behavioral profile against which to relate the neurophysiological, neuroradiological, and biochemical information that is gathered concurrently on these patients. The data can also provide neurobehaviorally-defined subgroups aimed at reducing variability in psychiatric diagnosis, treatment, and outcome.